A Mesh-Type Low RCS Reflectarray Antenna Based on Spoof Surface Plasmon Polariton

Abstract

This letter presents a low radar cross section (RCS) reflectarray antenna consisting of a feed horn and a spoof surface plasmon polariton (SSPP) reflector. The mesh-type reflector, composed of ${\rm{14\ \times \ 14}}$ bandstop elements, is transparent in the optical band. Owing to the SSPP modes excited by the metallic grating structures (MGSs), each element has high reflectivity in its stopband and high transmittivity in its passband. Moreover, the reflection phase of each element can be adjusted by varying the length of the MGSs. Therefore, the reflector can convert spherical waves into plane waves in the working band and transmit the out-of-band incident waves, thus obtaining low RCS properties. The simulated results indicate that the proposed antenna has a maximum gain of 25.2 dBi, a maximum aperture efficiency of 44.5%, and a 1 dB gain bandwidth of 13.9% (9.4-10.8 GHz). Compared to the reference antenna, the RCS of the proposed antenna is obviously reduced in the frequency ranges of 1.0-8.5 GHz and 12.0-19.0 GHz.